#down input{
    width: 420px;
    height: 50px;
    font-size: 14px;
    margin-top: 100px;
    margin-left: 5px;
}
#down div:nth-child(2) .b1{
    width: 240px;
    margin-top: 30px;
    margin-left: 5px;

}
#down div:nth-child(2) .b2{
    width: 140px;
    height: 42px;
    margin-left: 40px;
    background: #1E9FFF;
    color: white;
}
#down .b3{
    background: #1992EF;
    border-radius: 4px;
    color: white;
    font-size: 16px;
    margin-top: 20px;

}